The fabrication of ultrathin films with polymer precursors has been the basis for many advancements in materials science and nanotechnology.
Over the last decade, nanotechnology research has widely exploited “bottom up” assembly methods to construct advanced functional materials of tailored chemical and physical properties. One “bottom up” technique is the layer-by-layer (LbL) assembly technique. This method entails the sequential assembly of components from solution onto surfaces based on interactions such as electrostatic or hydrogen bonding interactions. However, while the LbL assembly technique permits the nanoscale engineering of materials, the process can be labour and time consuming as it typically involves the individual deposition of alternating polymers with complementary functionalities to construct the polymer assembly so reaction times of several hours or days are required to create the films. Such films can also be susceptible to disassembly under varying solution conditions that disrupt the electrostatic or hydrogen bonds.
Other methods reported for the fabrication of thin films and nanostructures are surface grafting methods, such as “grafting from” and “grafting to” methods. The “grafting from” approach involves initiation of a surface with an initiating moiety, which is then used to initiate the polymerisation of monomers from the surface. The “grafting to” approach utilizes end-functionalised polymers, which are then coupled to a complementary functional group present on a surface. A disadvantage of films fabricated by these techniques however is that the films lack mechanical rigidity. Furthermore, the grafted films are not structurally persistent if the underlying substrate is removed.
It would be desirable to provide a new process for preparing covalently cross-linked multilayer macromolecular films.
The discussion of documents, acts, materials, devices, articles and the like is included in this specification solely for the purpose of providing a context for the present invention. It is not suggested or represented that any or all of these matters formed part of the prior art base or were common general knowledge in the field relevant to the present invention as it existed before the priority date of each claim of this application.